1. Technical Field
The invention relates generally to telephones and more particularly to audibly annunciating information at a telephone or in proximity of a telephone.
2. Description of the Related Art
Caller Identification (hereinafter “caller ID”) is a feature provided by local phone companies that sends information from the telephone network to a telephone device between the first and second rings. The information that is sent varies. It generally includes, however, the calling telephone number and the name of the caller. This information is sent via the telephone line in a digital data packet that is usually Frequency Shift Keyed (hereinafter “FSK”) modulated. At the receiving telephone device the subscriber must be signed up for the caller ID service and must have a caller ID data receiver, i.e., a caller ID unit, connected to the telephone line in order to receive the digital data packet containing the caller ID information for the calling telephone device. The data receiver receives the FSK modulated digital data packet and provides a visual display of the information. In operation, the caller ID unit receives the FSK modulated digital data packet, demodulates it and converts the information into a stream of text characters that is then displayed, for example, on a liquid crystal display (LCD) provided either on the caller ID unit or which is integral to the telephone device itself. As discussed before, for an incoming call, the caller ID information that is displayed at the receiving side can include the name and number of the calling party among other types of information. The central office must have “caller ID capability” and the service must be enabled within the central office of the local telephone exchange. If, however, the central office does not have caller ID capability, the called party will receive a variety of messages including, for example, “out of area.”
Among the information that is displayed on the caller ID unit is the originating telephone number and the name listed in the directory under that number. In other words, the name that is displayed is the name that the telephone company has entered into a database and believes to be that of its customer. The number in the local central office database also aids another database lookup and thus associates the name in the directory with the number from where the call originates. The calling party's name and number information is transmitted through the central office and the telecommunication network and ultimately is displayed at the caller ID unit or on the telephone device itself. As discussed hereinbefore, such caller ID information is generally transmitted and displayed between the first and second rings. For caller ID to work properly in a telecommunication environment, the telecommunication network switches must be supported by Common Channel Signaling (CCS) and the party initiating the call must originate it from a single-channel line, a multi-channel trunk line with ANI/Calling Party ID. Further, if the originating line or caller blocks the transmission of the caller ID information, the receiving party will not be able to view the information or the receiving device will display, for example, “ANONYMOUS,” “NOT AVAILABLE” or “PRIVATE CALLER.”
Now turning to FIG. 1, one example of a caller ID system 10 is illustrated generally. The system 10 includes a calling telephone device 12 connected to a first central office switch 18 that originates a call to a first receiving telephone device 14 connected to a second central office switch 20. The call propagates through a telecommunication network 16 that provides a connection between the first central office switch 18 and the second central office switch 20. The receiving telephone device 14 includes a conventional caller ID unit 22 that is separate and detached from the telephone device 14.
FIG. 2 illustrates one embodiment of a conventional caller ID unit 22. The caller ID unit 22 can include, for example, a telephone line interface circuit 36, a demodulator circuit 38, a control circuit 40 and an alphanumeric display 42. The control circuit 40 can be a single chip computer or can be implemented using discrete integrated circuits depending on the specific application. The control circuit 40 includes, in the most general sense, a microprocessor 44, a memory circuit 46 and a read only memory circuit 48 (ROM). The control circuit 40 also includes a universal asynchronous receiver transmitter 52 (UART) and a baud rate generator 53. Also included are an address bus 50 and a data bus 54 for interconnecting the various units as shown and an address decoder 49 for selecting various peripheral devices that the control circuit 40 interfaces with such as, for example, the alphanumeric display 42.
In operation the caller ID unit 22 receives FSK modulated caller ID signals during an interval between intermittent ringing signals from the central office switch 20. The FSK modulated caller ID signals contain, for example, a channel seizure stream that is followed by a mark stream and then the actual caller ID information. The caller ID information can be sent in a Single Data Message Format (hereinafter “SDMF”) containing the calling number or in a Multiple Data Message Format (hereinafter “MDMF”) containing the calling number and the name associated with that number. The number and name fields may contain additional data to indicate that the caller has blocked the information or that the information is not available. The additional data includes, for example, single bit markers that are interpreted for display.
The FSK modulated caller ID signals are received at the tip 32 and ring 34 side of the telephone line. These signals are then passed through the telephone line interface circuit 36 where they are filtered and amplified. The filtered and amplified signals are then coupled to the FSK demodulator circuit 38 where the modulated signals are converted to a serial bit stream representation of the caller ID data message. The serial bit stream is then fed to the UART 52, which converts the serial bit stream into a parallel bit format. The parallel bit formatted stream is interpreted as a series of characters comprising the caller ID information data by the microprocessor 44. The microprocessor 44 then periodically updates the alphanumeric display 42 with each character comprising the parallel bit formatted stream. For additional information regarding the caller ID unit 22, reference is made to U.S. Pat. No. 4,582,956 to Doughty, which is herein incorporated by reference in its entirety.
Over the years the value of the caller ID unit 22 has been shadowed by the fact that the caller ID information is only provided to the recipient in the form of a visual display. The visual display of the caller ID information has much less value to the recipient if he or she happens to be out of the immediate vicinity of the display. For example, if the recipient is in another room and the telephone rings, the recipient must first locate the caller ID unit 22 before he or she can identify the caller. To address this need, several talking caller ID devices exist. Such devices, however, are not an integral part of the telephone and thus add to the number of appliances a user has to purchase and maintain. The talking caller ID devices do not provide a real-time announcement of the caller ID information and rely mainly on prerecorded messages and pre-stored information such as known telephone numbers. Furthermore, the talking caller ID devices do not provide a telephone ring signal capturing function such that the telephone remains silent until the talking caller ID device has received an entire caller ID information stream.
Therefore, there is a need in the art for an apparatus, system and method for communicating the caller ID information to a recipient in a format other than a visual display that is provided as an integral part of a telephone device. There is also a need to provide the caller ID information in a real-time format as the information is transmitted from the caller without relying on prerecorded messages and pre-stored information such as known telephone numbers. Furthermore, there is a need in the art for a telephone ring signal capturing function such that the caller ID device captures and holds the telephone ring signals until an entire caller ID information stream has been received.